Graphic: the problems facing the G20

Gordon Brown has called it a grand bargain, but when world leaders converge on London next month for a global summit on the ailing international economy, a £50 million bill may leave British taxpayers feeling it is anything but.

Five months of meticulous preparations by Whitehall will come to fruition at the ExCeL Centre on April 2 when a nondescript Thames-side conference hall, better known for the British Motor Show, plays host to what could be the most important event of Mr Brown’s career. On the north quayside of the Royal Victoria Dock, the Prime Minister will greet 22 leaders to discuss reviving the world economy, including President Obama on his first stop on a European visit.

The planning has been huge, but ministers have already been urged to reign in the bill for the summit. The Foreign and Commonwealth Office estimates it will come to £19 million, but some Whitehall insiders estimate it could reach £50 million.

Caroline Flint, the Europe Minister, has already defended the huge sums. “The costs of having the summit are far outweighed by the risks involved in not having it at all,” she has said.

Stansted airport and nearby military bases have been put on standby for the arrival of world leaders, while a huge ring of steel will be thrown around the conference venue itself.

The gathering has already mushroomed beyond the G20 group of leaders, as countries and regions fought to ensure they were not excluded. About 35 world leaders, including 10 regional and financial chiefs, have accepted invitations, including the chairmen of African, Asian and European groups of countries. They will be followed by a further 500 aides and advisers.

Yesterday the Tories broke ranks and questioned the cost. Greg Hands, a member of George Osborne’s Treasury team, said: “The cost of this will seem very high to hard-pressed families, especially at a time of extreme economic hardship and trillion-pound liabilities. The public will wonder if this is another example of the Government’s legendary inability to get value for money from their taxes.”

This followed a series of parliamentary answers that have laid bare the individual costs. These include a private film and events company to help to stage the summit, providing technical expertise, broadcasting equipment and staging, at a cost of £5.94 million; and co-ordinators hired at a predicted cost of £194,750 from PA Consulting, a company stripped of a Home Office contract last year after it lost a memory stick containing the details of thousands of criminals.

The dominance of the summit has been causing friction in Whitehall. No new money has been allocated for the event, meaning costs will be found from within existing departmental and police budgets, mostly divided between the Foreign Office and the Metropolitan Police.

Officials say that this compares favourably with the £12.7 million cost of the Gleneagles G8 summit in 2005 and the 2008 G8 summit in Japan, which cost an estimated $285 million.

Mr Brown is trying to make as much of an occasion as possible. The evening beforehand, he will host a reception and a “working dinner” in Downing Street for all the leaders. President Obama is expected to arrive after meeting the Queen. On the day itself, meetings will be held in private until the afternoon.

Afterwards, Mr Obama will hold talks with President Sarkozy of France and Angela Merkel, the German Chancellor, before flying to a Nato summit in Strasbourg.

Mr Brown edged closer to admitting mistakes in his handling of the economy yesterday as he predicted that the credit drought would ease in the months ahead. He again stopped short of an apology for the economic crisis but conceded that Britain’s system for regulating banks, which he set up as Chancellor, was not tough enough.

Pressed to apologise by callers to the BBC Radio 4 You and Yours programme, Mr Brown said he would not “shy away” from the decisions he made.

G20 and the groupies

— The Group of Twenty (G20) finance ministers and central bank governors was established in 1999

— Its goal was to bring together important industrialised and developing economies to discuss key issues in the global economy

— It consists of 19 of the largest national economies, plus the EU

— It has met only once before at heads of government level, in November last year in Washington at the invitation of President Bush. The London Summit on April 2 will be the second time

— Spain and the Netherlands were added to the November guest list and will also go to London, making 22 heads of government attending. There will also be regional leaders from Asia, Africa and Europe.

— The G20 has no full-time staff

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